Philadelphia heat wave won't relent for awhile

If you thought Monday hot, temperatures are forecast to climb to dangerously high levels the rest of the week.

Why it matters: Extreme heat can cause serious illness or death , and trigger utility disruptions knocking out air conditioning.

State of play: A heat dome shifting toward the Philly region will bring temps of about 94 on Tuesday and Wednesday, per the National Weather Service.

• A heat advisory is in effect through Thursday 6am when the heat index could make it feel near 100.

Then, Thursday is forecast to reach 97 before temps reach at least 100 on Friday and Saturday.

• An excessive heat watch stretches from Thursday through Sunday, where it could feel as hot as 105.

The big picture: Dozens of daily high-temperature records are in jeopardy, as are June hot streak milestones and hot overnight minimums across the Northeast.

• The heat wave could break the Philly region's monthly record of 102 .

How it works: Heat domes are strong ridges of high pressure that features sinking air below, which causes air to sink, temps to rise and rain chances to diminish. Air circulates about them in a clockwise direction.

The bottom line: The NWS advises drinking plenty of fluids, avoiding the sun, staying in air-conditioned spaces and checking on neighbors and relatives during the heat wave.

What's ahead: The NWS Weather Prediction Center said in a forecast discussion Monday the heat wave will likely continue beyond Friday, as the heat dome slides slowly south and elongates from west to east, but does not diminish completely.

• The NOAA climate outlook for June 29-July 12 shows an above-average likelihood of hotter-than-usual conditions across much of the country.